// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Hardware monitoring driver for UCD90xxx Sequencer and System Health
 * Controller series
 *
 * Copyright (C) 2011 Ericsson AB.
 */

#include <linux/debugfs.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/pmbus.h>
#include <linux/gpio/driver.h>
#include <linux/delay.h>
#include "wb_pmbus.h"

enum chips { ucd9000, ucd90120, ucd90124, ucd90160, ucd90320, ucd9090,
         ucd90910 };

#define UCD9000_MONITOR_CONFIG      0xd5
#define UCD9000_NUM_PAGES           0xd6
#define UCD9000_FAN_CONFIG_INDEX    0xe7
#define UCD9000_FAN_CONFIG          0xe8
#define UCD9000_MFR_STATUS          0xf3
#define UCD9000_GPIO_SELECT         0xfa
#define UCD9000_GPIO_CONFIG         0xfb
#define UCD9000_DEVICE_ID           0xfd

/* GPIO CONFIG bits */
#define UCD9000_GPIO_CONFIG_ENABLE        BIT(0)
#define UCD9000_GPIO_CONFIG_OUT_ENABLE    BIT(1)
#define UCD9000_GPIO_CONFIG_OUT_VALUE     BIT(2)
#define UCD9000_GPIO_CONFIG_STATUS        BIT(3)
#define UCD9000_GPIO_INPUT        0
#define UCD9000_GPIO_OUTPUT       1

#define UCD9000_MON_TYPE(x)       (((x) >> 5) & 0x07)
#define UCD9000_MON_PAGE(x)       ((x) & 0x1f)

#define UCD9000_MON_VOLTAGE       1
#define UCD9000_MON_TEMPERATURE   2
#define UCD9000_MON_CURRENT       3
#define UCD9000_MON_VOLTAGE_HW    4

#define UCD9000_NUM_FAN           4

#define UCD9000_GPIO_NAME_LEN     16
#define UCD9090_NUM_GPIOS         23
#define UCD901XX_NUM_GPIOS        26
#define UCD90320_NUM_GPIOS        84
#define UCD90910_NUM_GPIOS        26

#define UCD9000_DEBUGFS_NAME_LEN  24
#define UCD9000_GPI_COUNT         8
#define UCD90320_GPI_COUNT        32

#define UCD9000_RETRY_SLEEP_TIME          (10000)   /* 10ms */
#define UCD9000_RETRY_TIME                (3)
#define WB_DEV_NAME_MAX_LEN               (64)

static int g_wb_ucd9000_debug = 0;
static int g_wb_ucd9000_error = 0;

module_param(g_wb_ucd9000_debug, int, S_IRUGO | S_IWUSR);
module_param(g_wb_ucd9000_error, int, S_IRUGO | S_IWUSR);

#define WB_UDC9000_VERBOSE(fmt, args...) do {                                        \
    if (g_wb_ucd9000_debug) { \
        printk(KERN_INFO "[WB_UCD9000][VER][func:%s line:%d]\r\n"fmt, __func__, __LINE__, ## args); \
    } \
} while (0)

#define WB_UDC9000_ERROR(fmt, args...) do {                                        \
    if (g_wb_ucd9000_error) { \
        printk(KERN_ERR "[WB_UCD9000][ERR][func:%s line:%d]\r\n"fmt, __func__, __LINE__, ## args); \
    } \
} while (0)

struct ucd9000_data {
    u8 fan_data[UCD9000_NUM_FAN][I2C_SMBUS_BLOCK_MAX];
    struct pmbus_driver_info info;
#ifdef CONFIG_GPIOLIB
    struct gpio_chip gpio;
#endif
    struct dentry *debugfs;
};
#define to_ucd9000_data(_info) container_of(_info, struct ucd9000_data, info)

struct ucd9000_debugfs_entry {
    struct i2c_client *client;
    u8 index;
};

static int wb_i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, u8 *values)
{
    int rv, i;

    for(i = 0; i < UCD9000_RETRY_TIME; i++) {
        rv = i2c_smbus_read_block_data(client, command, values);
        if(rv >= 0){
            return rv;
        }
        usleep_range(UCD9000_RETRY_SLEEP_TIME, UCD9000_RETRY_SLEEP_TIME + 1);
    }
    WB_UDC9000_ERROR("read_block_data failed. nr:%d, addr:0x%x, reg:0x%x, rv:%d.",
        client->adapter->nr, client->addr, command, rv);
    return rv;
}

static int ucd9000_get_fan_config(struct i2c_client *client, int fan)
{
    int fan_config = 0;
    struct ucd9000_data *data
      = to_ucd9000_data(wb_pmbus_get_driver_info(client));

    if (data->fan_data[fan][3] & 1)
        fan_config |= PB_FAN_2_INSTALLED;   /* Use lower bit position */

    /* Pulses/revolution */
    fan_config |= (data->fan_data[fan][3] & 0x06) >> 1;

    return fan_config;
}

static int ucd9000_read_byte_data(struct i2c_client *client, int page, int reg)
{
    int ret = 0;
    int fan_config;

    switch (reg) {
    case PMBUS_FAN_CONFIG_12:
        if (page > 0)
            return -ENXIO;

        ret = ucd9000_get_fan_config(client, 0);
        if (ret < 0)
            return ret;
        fan_config = ret << 4;
        ret = ucd9000_get_fan_config(client, 1);
        if (ret < 0)
            return ret;
        fan_config |= ret;
        ret = fan_config;
        break;
    case PMBUS_FAN_CONFIG_34:
        if (page > 0)
            return -ENXIO;

        ret = ucd9000_get_fan_config(client, 2);
        if (ret < 0)
            return ret;
        fan_config = ret << 4;
        ret = ucd9000_get_fan_config(client, 3);
        if (ret < 0)
            return ret;
        fan_config |= ret;
        ret = fan_config;
        break;
    default:
        ret = -ENODATA;
        break;
    }
    return ret;
}

static const struct i2c_device_id ucd9000_id[] = {
    {"wb_ucd9000", ucd9000},
    {"wb_ucd90120", ucd90120},
    {"wb_ucd90124", ucd90124},
    {"wb_ucd90160", ucd90160},
    {"wb_ucd90320", ucd90320},
    {"wb_ucd9090", ucd9090},
    {"wb_ucd90910", ucd90910},
    {}
};
MODULE_DEVICE_TABLE(i2c, ucd9000_id);

static const struct of_device_id __maybe_unused ucd9000_of_match[] = {
    {
        .compatible = "ti,wb_ucd9000",
        .data = (void *)ucd9000
    },
    {
        .compatible = "ti,wb_ucd90120",
        .data = (void *)ucd90120
    },
    {
        .compatible = "ti,wb_ucd90124",
        .data = (void *)ucd90124
    },
    {
        .compatible = "ti,wb_ucd90160",
        .data = (void *)ucd90160
    },
    {
        .compatible = "ti,wb_ucd90320",
        .data = (void *)ucd90320
    },
    {
        .compatible = "ti,wb_ucd9090",
        .data = (void *)ucd9090
    },
    {
        .compatible = "ti,wb_ucd90910",
        .data = (void *)ucd90910
    },
    { },
};
MODULE_DEVICE_TABLE(of, ucd9000_of_match);

#ifdef CONFIG_GPIOLIB
static int ucd9000_gpio_read_config(struct i2c_client *client,
                    unsigned int offset)
{
    int ret;

    /* No page set required */
    ret = i2c_smbus_write_byte_data(client, UCD9000_GPIO_SELECT, offset);
    if (ret < 0)
        return ret;

    return i2c_smbus_read_byte_data(client, UCD9000_GPIO_CONFIG);
}

static int ucd9000_gpio_get(struct gpio_chip *gc, unsigned int offset)
{
    struct i2c_client *client  = gpiochip_get_data(gc);
    int ret;

    ret = ucd9000_gpio_read_config(client, offset);
    if (ret < 0)
        return ret;

    return !!(ret & UCD9000_GPIO_CONFIG_STATUS);
}

static void ucd9000_gpio_set(struct gpio_chip *gc, unsigned int offset,
                 int value)
{
    struct i2c_client *client = gpiochip_get_data(gc);
    int ret;

    ret = ucd9000_gpio_read_config(client, offset);
    if (ret < 0) {
        dev_dbg(&client->dev, "failed to read GPIO %d config: %d\n",
            offset, ret);
        return;
    }

    if (value) {
        if (ret & UCD9000_GPIO_CONFIG_STATUS)
            return;

        ret |= UCD9000_GPIO_CONFIG_STATUS;
    } else {
        if (!(ret & UCD9000_GPIO_CONFIG_STATUS))
            return;

        ret &= ~UCD9000_GPIO_CONFIG_STATUS;
    }

    ret |= UCD9000_GPIO_CONFIG_ENABLE;

    /* Page set not required */
    ret = i2c_smbus_write_byte_data(client, UCD9000_GPIO_CONFIG, ret);
    if (ret < 0) {
        dev_dbg(&client->dev, "Failed to write GPIO %d config: %d\n",
            offset, ret);
        return;
    }

    ret &= ~UCD9000_GPIO_CONFIG_ENABLE;

    ret = i2c_smbus_write_byte_data(client, UCD9000_GPIO_CONFIG, ret);
    if (ret < 0)
        dev_dbg(&client->dev, "Failed to write GPIO %d config: %d\n",
            offset, ret);
}

static int ucd9000_gpio_get_direction(struct gpio_chip *gc,
                      unsigned int offset)
{
    struct i2c_client *client = gpiochip_get_data(gc);
    int ret;

    ret = ucd9000_gpio_read_config(client, offset);
    if (ret < 0)
        return ret;

    return !(ret & UCD9000_GPIO_CONFIG_OUT_ENABLE);
}

static int ucd9000_gpio_set_direction(struct gpio_chip *gc,
                      unsigned int offset, bool direction_out,
                      int requested_out)
{
    struct i2c_client *client = gpiochip_get_data(gc);
    int ret, config, out_val;

    ret = ucd9000_gpio_read_config(client, offset);
    if (ret < 0)
        return ret;

    if (direction_out) {
        out_val = requested_out ? UCD9000_GPIO_CONFIG_OUT_VALUE : 0;

        if (ret & UCD9000_GPIO_CONFIG_OUT_ENABLE) {
            if ((ret & UCD9000_GPIO_CONFIG_OUT_VALUE) == out_val)
                return 0;
        } else {
            ret |= UCD9000_GPIO_CONFIG_OUT_ENABLE;
        }

        if (out_val)
            ret |= UCD9000_GPIO_CONFIG_OUT_VALUE;
        else
            ret &= ~UCD9000_GPIO_CONFIG_OUT_VALUE;

    } else {
        if (!(ret & UCD9000_GPIO_CONFIG_OUT_ENABLE))
            return 0;

        ret &= ~UCD9000_GPIO_CONFIG_OUT_ENABLE;
    }

    ret |= UCD9000_GPIO_CONFIG_ENABLE;
    config = ret;

    /* Page set not required */
    ret = i2c_smbus_write_byte_data(client, UCD9000_GPIO_CONFIG, config);
    if (ret < 0)
        return ret;

    config &= ~UCD9000_GPIO_CONFIG_ENABLE;

    return i2c_smbus_write_byte_data(client, UCD9000_GPIO_CONFIG, config);
}

static int ucd9000_gpio_direction_input(struct gpio_chip *gc,
                    unsigned int offset)
{
    return ucd9000_gpio_set_direction(gc, offset, UCD9000_GPIO_INPUT, 0);
}

static int ucd9000_gpio_direction_output(struct gpio_chip *gc,
                     unsigned int offset, int val)
{
    return ucd9000_gpio_set_direction(gc, offset, UCD9000_GPIO_OUTPUT,
                      val);
}

static void ucd9000_probe_gpio(struct i2c_client *client,
                   const struct i2c_device_id *mid,
                   struct ucd9000_data *data)
{
    int rc;

    switch (mid->driver_data) {
    case ucd9090:
        data->gpio.ngpio = UCD9090_NUM_GPIOS;
        break;
    case ucd90120:
    case ucd90124:
    case ucd90160:
        data->gpio.ngpio = UCD901XX_NUM_GPIOS;
        break;
    case ucd90320:
        data->gpio.ngpio = UCD90320_NUM_GPIOS;
        break;
    case ucd90910:
        data->gpio.ngpio = UCD90910_NUM_GPIOS;
        break;
    default:
        return; /* GPIO support is optional. */
    }

    /*
     * Pinmux support has not been added to the new gpio_chip.
     * This support should be added when possible given the mux
     * behavior of these IO devices.
     */
    data->gpio.label = client->name;
    data->gpio.get_direction = ucd9000_gpio_get_direction;
    data->gpio.direction_input = ucd9000_gpio_direction_input;
    data->gpio.direction_output = ucd9000_gpio_direction_output;
    data->gpio.get = ucd9000_gpio_get;
    data->gpio.set = ucd9000_gpio_set;
    data->gpio.can_sleep = true;
    data->gpio.base = -1;
    data->gpio.parent = &client->dev;

    rc = devm_gpiochip_add_data(&client->dev, &data->gpio, client);
    if (rc)
        dev_warn(&client->dev, "Could not add gpiochip: %d\n", rc);
}
#else
static void ucd9000_probe_gpio(struct i2c_client *client,
                   const struct i2c_device_id *mid,
                   struct ucd9000_data *data)
{
}
#endif /* CONFIG_GPIOLIB */

#ifdef CONFIG_DEBUG_FS
static int ucd9000_get_mfr_status(struct i2c_client *client, u8 *buffer)
{
    int ret = wb_pmbus_set_page(client, 0, 0xff);

    if (ret < 0)
        return ret;

    return wb_i2c_smbus_read_block_data(client, UCD9000_MFR_STATUS, buffer);
}

static int ucd9000_debugfs_show_mfr_status_bit(void *data, u64 *val)
{
    struct ucd9000_debugfs_entry *entry = data;
    struct i2c_client *client = entry->client;
    u8 buffer[I2C_SMBUS_BLOCK_MAX];
    int ret, i;

    ret = ucd9000_get_mfr_status(client, buffer);
    if (ret < 0)
        return ret;

    /*
     * GPI fault bits are in sets of 8, two bytes from end of response.
     */
    i = ret - 3 - entry->index / 8;
    if (i >= 0)
        *val = !!(buffer[i] & BIT(entry->index % 8));

    return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(ucd9000_debugfs_mfr_status_bit,
             ucd9000_debugfs_show_mfr_status_bit, NULL, "%1lld\n");

static ssize_t ucd9000_debugfs_read_mfr_status(struct file *file,
                           char __user *buf, size_t count,
                           loff_t *ppos)
{
    struct i2c_client *client = file->private_data;
    u8 buffer[I2C_SMBUS_BLOCK_MAX];
    char str[(I2C_SMBUS_BLOCK_MAX * 2) + 2];
    char *res;
    int rc;

    rc = ucd9000_get_mfr_status(client, buffer);
    if (rc < 0)
        return rc;

    res = bin2hex(str, buffer, min(rc, I2C_SMBUS_BLOCK_MAX));
    *res++ = '\n';
    *res = 0;

    return simple_read_from_buffer(buf, count, ppos, str, res - str);
}

static const struct file_operations ucd9000_debugfs_show_mfr_status_fops = {
    .llseek = noop_llseek,
    .read = ucd9000_debugfs_read_mfr_status,
    .open = simple_open,
};

static int ucd9000_init_debugfs(struct i2c_client *client,
                const struct i2c_device_id *mid,
                struct ucd9000_data *data)
{
    struct dentry *debugfs;
    struct ucd9000_debugfs_entry *entries;
    int i, gpi_count;
    char name[UCD9000_DEBUGFS_NAME_LEN];

    debugfs = wb_pmbus_get_debugfs_dir(client);
    if (!debugfs)
        return -ENOENT;

    data->debugfs = debugfs_create_dir(client->name, debugfs);
    if (!data->debugfs)
        return -ENOENT;

    /*
     * Of the chips this driver supports, only the UCD9090, UCD90160,
     * UCD90320, and UCD90910 report GPI faults in their MFR_STATUS
     * register, so only create the GPI fault debugfs attributes for those
     * chips.
     */
    if (mid->driver_data == ucd9090 || mid->driver_data == ucd90160 ||
        mid->driver_data == ucd90320 || mid->driver_data == ucd90910) {
        gpi_count = mid->driver_data == ucd90320 ? UCD90320_GPI_COUNT
                             : UCD9000_GPI_COUNT;
        entries = devm_kcalloc(&client->dev,
                       gpi_count, sizeof(*entries),
                       GFP_KERNEL);
        if (!entries)
            return -ENOMEM;

        for (i = 0; i < gpi_count; i++) {
            entries[i].client = client;
            entries[i].index = i;
            scnprintf(name, UCD9000_DEBUGFS_NAME_LEN,
                  "gpi%d_alarm", i + 1);
            debugfs_create_file(name, 0444, data->debugfs,
                        &entries[i],
                        &ucd9000_debugfs_mfr_status_bit);
        }
    }

    scnprintf(name, UCD9000_DEBUGFS_NAME_LEN, "mfr_status");
    debugfs_create_file(name, 0444, data->debugfs, client,
                &ucd9000_debugfs_show_mfr_status_fops);

    return 0;
}
#else
static int ucd9000_init_debugfs(struct i2c_client *client,
                const struct i2c_device_id *mid,
                struct ucd9000_data *data)
{
    return 0;
}
#endif /* CONFIG_DEBUG_FS */

static int ucd9000_probe(struct i2c_client *client)
{
    u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
    char wb_device_name[WB_DEV_NAME_MAX_LEN];
    struct ucd9000_data *data;
    struct pmbus_driver_info *info;
    const struct i2c_device_id *mid;
    enum chips chip;
    int i, ret;

    if (!i2c_check_functionality(client->adapter,
                     I2C_FUNC_SMBUS_BYTE_DATA |
                     I2C_FUNC_SMBUS_BLOCK_DATA))
        return -ENODEV;

    ret = wb_i2c_smbus_read_block_data(client, UCD9000_DEVICE_ID,
                    block_buffer);
    if (ret < 0) {
        dev_err(&client->dev, "Failed to read device ID\n");
        return ret;
    }
    block_buffer[ret] = '\0';
    dev_info(&client->dev, "Device ID %s\n", block_buffer);

    mem_clear(wb_device_name, sizeof(wb_device_name));
    snprintf(wb_device_name, sizeof(wb_device_name), "wb_%s", block_buffer);

    for (mid = ucd9000_id; mid->name[0]; mid++) {
        if (!strncasecmp(mid->name, wb_device_name, strlen(mid->name)))
            break;
    }
    if (!mid->name[0]) {
        dev_err(&client->dev, "Unsupported device\n");
        return -ENODEV;
    }

    if (client->dev.of_node)
        chip = (enum chips)of_device_get_match_data(&client->dev);
    else
        chip = mid->driver_data;

    if (chip != ucd9000 && strcmp(client->name, mid->name) != 0)
        dev_notice(&client->dev,
               "Device mismatch: Configured %s, detected %s\n",
               client->name, mid->name);

    data = devm_kzalloc(&client->dev, sizeof(struct ucd9000_data),
                GFP_KERNEL);
    if (!data)
        return -ENOMEM;
    info = &data->info;

    ret = i2c_smbus_read_byte_data(client, UCD9000_NUM_PAGES);
    if (ret < 0) {
        dev_err(&client->dev,
            "Failed to read number of active pages\n");
        return ret;
    }
    info->pages = ret;
    if (!info->pages) {
        dev_err(&client->dev, "No pages configured\n");
        return -ENODEV;
    }

    /* The internal temperature sensor is always active */
    info->func[0] = PMBUS_HAVE_TEMP;

    /* Everything else is configurable */
    ret = wb_i2c_smbus_read_block_data(client, UCD9000_MONITOR_CONFIG,
                    block_buffer);
    if (ret <= 0) {
        dev_err(&client->dev, "Failed to read configuration data\n");
        return -ENODEV;
    }
    for (i = 0; i < ret; i++) {
        int page = UCD9000_MON_PAGE(block_buffer[i]);

        if (page >= info->pages)
            continue;

        switch (UCD9000_MON_TYPE(block_buffer[i])) {
        case UCD9000_MON_VOLTAGE:
        case UCD9000_MON_VOLTAGE_HW:
            info->func[page] |= PMBUS_HAVE_VOUT
              | PMBUS_HAVE_STATUS_VOUT;
            break;
        case UCD9000_MON_TEMPERATURE:
            info->func[page] |= PMBUS_HAVE_TEMP2
              | PMBUS_HAVE_STATUS_TEMP;
            break;
        case UCD9000_MON_CURRENT:
            info->func[page] |= PMBUS_HAVE_IOUT
              | PMBUS_HAVE_STATUS_IOUT;
            break;
        default:
            break;
        }
    }

    /* Fan configuration */
    if (mid->driver_data == ucd90124) {
        for (i = 0; i < UCD9000_NUM_FAN; i++) {
            i2c_smbus_write_byte_data(client,
                          UCD9000_FAN_CONFIG_INDEX, i);
            ret = wb_i2c_smbus_read_block_data(client,
                            UCD9000_FAN_CONFIG,
                            data->fan_data[i]);
            if (ret < 0)
                return ret;
        }
        i2c_smbus_write_byte_data(client, UCD9000_FAN_CONFIG_INDEX, 0);

        info->read_byte_data = ucd9000_read_byte_data;
        info->func[0] |= PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12
          | PMBUS_HAVE_FAN34 | PMBUS_HAVE_STATUS_FAN34;
    }

    ucd9000_probe_gpio(client, mid, data);

    ret = wb_pmbus_do_probe(client, info);
    if (ret)
        return ret;

    ret = ucd9000_init_debugfs(client, mid, data);
    if (ret)
        dev_warn(&client->dev, "Failed to register debugfs: %d\n",
             ret);

    return 0;
}

/* This is the driver that will be inserted */
static struct i2c_driver ucd9000_driver = {
    .driver = {
        .name = "wb_ucd9000",
        .of_match_table = of_match_ptr(ucd9000_of_match),
    },
    .probe_new = ucd9000_probe,
    .remove = wb_pmbus_do_remove,
    .id_table = ucd9000_id,
};

module_i2c_driver(ucd9000_driver);

MODULE_AUTHOR("support");
MODULE_DESCRIPTION("PMBus driver for TI UCD90xxx");
MODULE_LICENSE("GPL");
